Frequencies for first 10,000 rows of drugres2 variable in person dataset :

  DRUG TEST |
  RESULTS-2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,640       96.40       96.40
          1 |         90        0.90       97.30
        128 |          2        0.02       97.32
        155 |          1        0.01       97.33
        177 |          1        0.01       97.34
        208 |          2        0.02       97.36
        295 |          1        0.01       97.37
        300 |          1        0.01       97.38
        304 |          2        0.02       97.40
        307 |          1        0.01       97.41
        308 |          1        0.01       97.42
        313 |          1        0.01       97.43
        321 |          3        0.03       97.46
        351 |          1        0.01       97.47
        358 |          1        0.01       97.48
        367 |          1        0.01       97.49
        401 |          2        0.02       97.51
        402 |          2        0.02       97.53
        407 |         19        0.19       97.72
        417 |         23        0.23       97.95
        603 |          2        0.02       97.97
        605 |          4        0.04       98.01
        606 |          3        0.03       98.04
        702 |          2        0.02       98.06
        825 |          1        0.01       98.07
        996 |         16        0.16       98.23
        997 |          2        0.02       98.25
        998 |          1        0.01       98.26
        999 |        174        1.74      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016